The present invention relates generally to a tillage implement and more specifically to a tillage implement with disk or coulter gang assemblies.
Tillage implements having both forward disk or coulter gang assemblies and rearward plow tools such as twisted shovels or cultivator sweeps are commonly used in stubble-mulch and deep fallow tillage operations. Disk or coulter blades cut the stubble or stalks and trash ahead of the plow tools, and the plow tools rip down through the plow-soil layer to open the soil so air and water can get in. Such implements leave the surface of the soil open and blended with residues that protect the topsoil. The residues decompose faster into humus, and thereby create drought resistance and stronger crop root growth the following year. The soil surface is left moderately ridgy to give moisture a chance to soak in rather than run off. Wind erosion is kept to a minimum by the crop residue and the ridges left by the plow tools. The commercially available John Deere 1710 Mulch Tiller is an example of such a tillage implement.
A typical mulch tiller or similar type implement includes disk or coulter gang assemblies which are supported at the forward end of a main frame assembly. Tool-carrying shank assemblies are mounted at the rearward portion of the main frame. Changing the relative depth of the gangs and the standard assemblies required changing the relative height of the front and rear portions of the frame. In addition, a leveling adjustment is required on the front hitch assembly to maintain the proper attitude of the entire frame assembly both in the transport and in the field-working positions.
The gangs on the aforementioned implements are either mounted relatively ridgidly with respect to the frame assembly or else are mounted with spring assemblies providing a short tripping distance with the downward force exerted by the trip assemblies increasing significantly as the gangs move upwardly and closer to the frame. Such gang mounting arrangements result in uneven penetration of the disks or coulters, and when rough terrain or obstacles are encountered, upward movement of the gangs can actually lift the frame or remove a significant portion of the weight from the frame so that the rear tools do not penetrate to the desired level. The previous implements are difficult to balance, that is, to provide a nearly constant down force both at the rear and front portions of the frame in varying soil conditions and terrain. The relative inflexibility of the gangs results in the individual blades or coulters supporting a disproportionate amount of the implement weight. It is not uncommon for disks or coulters or gang bearings to break. The front portion of the frame often has to be adjusted with respect to the rear portion to maintain both the proper cutting action of the disks or coulters and to maintain the proper penetrating depth of the earth-working tools as soil conditions change. With the previous implement designs which utilize a main frame assembly with relatively adjustable front and rear portions, wide implements could not be practically designed since the adjustable frame portions cannot easily accommodate pivotally connected outrigger sections.
It is therefore an object of the present invention to provide a tillage implement with improved trash-sizing and soil-penetrating characteristics in various soil conditions and terrain. It is a further object to provide such an implement which has improved trash and soil flow for better incorporation.
It is a further object to provide a tillage implement with forward trash-sizing gangs and rearward earth-working tools wherein the weight of the total implement is properly distributed on both the gangs and the rear tools, even in rough terrain and varying soil conditions. It is another object to provide such an implement utilizing forward coulter or disk gang assemblies rockably mounted on the frame which provide reliable trash sizing relatively independently of the distance between the frame and the surface of the soil.
It is another object of the invention to provide a disk or coulter gang assembly wherein the gang is spring loaded downwardly and can trip up over obstacles, and wherein a relatively constant level downward force is maintained regardless of the trip position of the gang. It is another object to provide a disk or coulter gang assembly which can accommodate rough terrain or variations in soil conditions better than previously available gangs, and which provides a reduced incidence of breakage in the gang assembly.
It is still another object of the present invention to provide a tillage implement which can accommodate either straight coulter or angled disk gangs of various widths, but which still utilizes a standard main frame, depth control, and hitch assembly to reduce manufacturing costs and permit convenient modification of the working width of the implement.
It is yet another object of the present invention to provide a trash-sizing and soil-penetrating implement which includes disk or coulter gang assemblies, wherein the implement has a main frame which easily accommodates added weights without significantly affecting the down pressure on the gangs and without significantly reducing underframe clearance.
It is another object of the invention to provide an improved frame assembly for a multiple-tool tillage implement. It is a further object to provide such a frame with diagonal structure in line with the forward hitch to provide a strong backbone for the implement while at the same time maintaining good underframe clearance.
It is still another object of the invention to provide an improved tillage implement with trash-sizing and soil-penetrating tools wherein lift and leveling linkages are maintained substantially below the level of the main frame.
It is yet a further object of the invention to provide a compact, stable trash-sizing and soil-penetrating implement which uses a single main frame and which requires fewer leveling adjustments than at least some of the previously available implements.
It is another object to provide such an implement with an improved frame which is easier to package for shipment and to assemble than previously available frames.
In accordance with the above objects, a rectangular, substantially rigid main frame assembly includes a forward portion supporting a plurality of transversely spaced disk or coulter gang assemblies. Each assembly includes at least two spring trip bracket units connected to the frame and supporting a generally transverse gang tube. Standards extend downwardly and rearwardly from the gang tube and terminate in disk gang bearings which rotatably support the disk or coulter gang. The spring bracket permits the gang tube to be torqued upwardly as forces act against the disks or coulters. The geometry of the spring bracket provides a relatively constant trip force between the lowermost and uppermost positions of the disk gang therefore making the down pressure on the gang relatively independent of the distance between the main frame and the top of the soil. The spring brackets may be connected directly to the front transverse bar of the main frame when a transverse arrangement of coulters is utilized. Alternatively, stub-bars can be bolted to the fore-and-aft components of the main frame to support individual disk gangs at an angle, preferably approximately fourteen degrees from the transverse direction.
The rear portion of the frame supports a plurality of transversely spaced heavy-duty spring trip shank assemblies carrying deep penetration tillage tools. The standards have a high initial trip force level, and the level first increases as the standard trips upwardly. After reaching an intermediate tripped position, the trip force begins decreasing to permit large obstacles to be cleared. The initial increase in trip force provides for positive reentry of the earth-working tool. Concave twisted shovels are provided on the spring trip shank assemblies for improved soil flow and trash incorporation. The individual tripping action coupled with the level trip force curve of the gang assemblies provide a substantially uniform and properly distributed down force on both the disks or coulters and the earth-working tools to properly size trash and to maintain constant deep soil penetration of the shovels, even in rough terrain or where obstacles are encountered.
The frame includes upper diagonal beam structure and a lower weldment which can be compactly packaged for shipment and easily assembled. Good ground clearance is provided beneath the frame. The lift assembly and leveling linkages are primarily contained below the top of the frame for a neater appearance and for more positive depth adjusting action. The upper diagonal beam structure forms a natural extension of the forward hitch for good draft load distribution along the frame. Suitcase-type weights can be conveniently supported on the beam structure in an accommodation space defined by the rearward portion of the frame. The gang support arrangement including the spring brackets provides a relatively even down pressure on the disk or coulter gangs to provide uniform trash sizing in differing terrain and soil conditions. The constant down pressure together with the ability of an individual gang assembly to trip independently of the remainder of the gangs advantageously maintain a relatively constant down pressure for the earth-working tools, even when additional weights are added. Disks or coulters can move upwardly over relatively large obstacles and are less likely to break. Disk scrapers are supported by the gang tube rather than by an individual scraper support bar so that the distance the gangs can trip is increased by eliminating the interference that existed between the frame and support bar with at least some of the previous implements.
The present design permits use of either angled disk gangs or straight blade coulter gangs of numerous different widths utilizing the same depth control, main frame and hitch components. The main frame structure easily accepts folding outrigger sections so that relatively wide implements can be manufactured. In a folding implement where more than one angled disk gang assembly is utilized on a flexible pivoting outrigger frame, the gangs are angled in opposite directions to balance side forces.
These and other objects, features and advantages of the present invention will become apparent from the detailed description below when taken with the accompanying drawings.